6066 (1960-1966) GMC Truck Club Bitcoin now accepted here! 
Pay Dues
Pay Dues or become a Site Supporter
 



Go Back   6066 (1960-1966) GMC Truck Club > 6066 GMC Truck Club Forum > GMC V6 and V12 Engines
#Sponsored

GMC V6 and V12 Engines Engine repair and rebuilding

Reply
 
Thread Tools
  #1  
Old March 15th, 2015, 04:50 PM
TJ's GMC's Avatar
TJ's GMC TJ's GMC is offline
Senior Member
 
Join Date: Mar 2015
Location: Cave Junction, Oregon
Truck: 1964 GMC 1500 LWB Wideside 305E V6.
Posts: 1,341
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 402
TJ's GMC is on a distinguished road
Default Do the 351M heads have larger valves?

So I've been told that the 351 heads will bolt onto a 305 and was wondering..do the 351 magnum heads have larger valves besides larger ports?
__________________
"Excuse the rust I use my truck"
1964 GMC 1500 305E/sm420 4 barrel intake mod and dual exhaust.
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1964 Chevy C20 292/SM420
1966 Chevy C10 292 hotrod 6/TKO600


My youtube channel aka Military Chevy:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #2  
Old March 15th, 2015, 05:22 PM
bigblockv6 bigblockv6 is offline
Senior Member
 
Join Date: Jan 2013
Location: Rohnert Park, ca.
Truck: 1968 KM2500
Posts: 1,325
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 418
bigblockv6 will become famous soon enoughbigblockv6 will become famous soon enough
Default Re: Do the 351M heads have larger valves?

Magnum heads do have larger intake and exhaust valves from the 305 heads but will also lower the compression when installed on the 305. Also all Magnum heads are the same regardless of the engines displacement. You would be better off replacing the 305 with a larger 351 or 401M V6.
Reply With Quote
  #3  
Old March 15th, 2015, 09:39 PM
TJ's GMC's Avatar
TJ's GMC TJ's GMC is offline
Senior Member
 
Join Date: Mar 2015
Location: Cave Junction, Oregon
Truck: 1964 GMC 1500 LWB Wideside 305E V6.
Posts: 1,341
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 402
TJ's GMC is on a distinguished road
Default Re: Do the 351M heads have larger valves?

It's crossed my mind to do a swap, but I'm a guy who likes to hop up stock engines. Did a 292 I6 in my chevy...coulda gone the 350 rout like everyone else in this world has but liked the 292 so hopped it up and will embarrass 350's with it now. The 305 I don't want to make a rpm engine out of, but just make it better. Heard of some perrty cool mods that people have done. Thanks for the response!
__________________
"Excuse the rust I use my truck"
1964 GMC 1500 305E/sm420 4 barrel intake mod and dual exhaust.
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1964 Chevy C20 292/SM420
1966 Chevy C10 292 hotrod 6/TKO600


My youtube channel aka Military Chevy:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Valves and Heads Archiver Previous Forum Posts 0 January 7th, 2010 08:15 AM
Re: [6066 GMC] Valves and Heads Archiver Previous Forum Posts 0 January 7th, 2010 01:17 AM
Re: [6066 GMC] Valves and Heads Archiver Previous Forum Posts 0 January 7th, 2010 01:14 AM
305 vs 351M Heads Archiver Previous Forum Posts 0 November 12th, 2007 01:32 AM
351M HEADS Archiver Previous Forum Posts 0 July 13th, 2005 02:51 AM


All times are GMT +1. The time now is 11:24 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd 921731597221|1730456684|0